Troweling device



April 21, c B slE TROWELING DEVICE 3 Sheets-Sheet 1 Filed July 15. 1955 INVENTOR. BY 6302 2: QB-2W2 HIS ATTOPN EYJ April 21, 1959 v vc:. B. SIEBER ,8

' TROWELING DEVICE Filed July 15. 1955 1 3 sheets-sheet 2 -I llIlllll fi I I INVIENTOR.

v CZar/Zx/i ier WWW HIS ATTOFNEYS' April 21, 1959- c.B. SIEBER TROWELI-NG DEVICE Filed July 13. 1955 3 Sheets-Sheet 3 INVENTOR. j BY Clay/$5 @Jz'eier HIS\ ATTORNEYS United States Patent i TROWELING DEVICE Charles B. Sieber, Villa Park, Ill., assignor to Elmer R. Stitt, Dayton, and William J. Miller, Kettering, Ohio Application July 13, 1955, Serial No. 521,702

3 Claims. (Cl. 94-45) nerable parts of the adjusting mechanism are housed in i such a manner that mortar spilled on the mechanism will not interfere with the operation thereof.

Another object of this invention is to provide a mounting mechanism consisting 'of an integral frame structure of tubular members that are light in weight and at the same time very strong and rigid.

Another object of this invention is to provide a prime mover and a reduction gear mechanism having the combined center of gravity aligned with the axis of the drive shaft.

Other objects and advantages reside in the construction of parts, the combination thereof and the mode of operation, as will become more apparent from the following description.

Referring to the drawings,

Figure 1 is a top plan view of the troweling device.

Figure 2 is a side elevational view.

Figure 3 is a cross sectional view, with parts broken away, taken substantially on the section line 33 of Figure 2.

Figure 4 is a cross sectional view, with parts broken away, taken substantially on the section line 44 of Figure 3.

Figure 5 is a fragmentary, cross sectional view, taken substantially on the section line 55 of Figure 4.

Figure 6 is a cross sectional view, taken substantially on the section line 66 of Figure 3.

Figure 7 is :a cross sectional View, taken substantially on the section line 7-7 of Figure 3.

Figure 8 is a fragmentary, cross sectional view, with parts broken away, taken substantially on the section line 88 of Figure 3.

Referring to the drawings, the reference character 10 designates a part of a frame consisting of tubular members integral with a handle 12 terminating in hand grip portions 14. A plurality of tubular arms 16, downwardly and outwardly directed, support a tubular ring 18.

A prime mover 20, shown rather schematically, which may be an internal combustion engine or an electric motor, is mounted on an engine support casting 22 which is,

in turn, mounted on the frame 10. If an engine is used, the longitudinal axis of the cylinder or cylinders is preferably perpendicular to the axis of rotation of the trowel blades. This prime mover 20 is connected through the engine support casting 22 and a gear box 23 to a down- Patented Apr. 21, 1959 ice 2 wardly projecting shaft 30, shown in Figures 3, 4 and 8. Most of the structure described thus far may be referred to as conventional, with the possible exception of the particular arrangement of the frame structure, the arrangement of the engine and the center of gravity thereof.

The lower end of the shaft 30 has fixedly mounted thereto a centrally disposed body member 32 that includes 'a disc-like portion 32a. A plurality of hollow cylindrical portions 40 are integral with the disc portion 32a. As best seen in- Figure 3, the longitudinal axes of the cylindrical portions 40 are offset with respect to the longitudinal axis of the shaft 30. Furthermore, the cylindrical portions 40 are offset forward of the shaft 30 when taking into consideration the direction of rotation of the shaft 30 and the member 32 supported thereon, as indicated by the 'arrow shown in Figure 3.

Housing members 42, which may consist of conventional metallic pipes, are mounted in the cylindrical portions 40 [and held in position by suitable set screws 44. The outer diameter of members 42 is substantially equal to the diameter of the bore of the cylindrical portions 40. Each of the tubular housing members 42 has rotatably mounted on the outer end thereof a bracket 50. Each bracket 50 has 'a rearwardly extending portion 52 provided with cars 54 having apertures receiving bolts 56 threadedly engaging a bar 58. The longitudinal axis of the bar 58 is offset to the rear of the :axis of the shaft 30. Each bar 58 has mounted thereon a trowel blade 60. The extreme end margins of the trowel blades are deflected upwardly at 62, 'as best seen in Figure 4. The axis of each housing member 42 and its bar 58 are parallel and normally in substantially horizontal planes.

It is quite essential to adjust the angle of inclination of the trowel blades. If, for example, the mortar has not been initially trowelled or floated, the angle of inclination would be far difieren-t than when the machine finishing operation is being given to the surface. Furthermore, it is quite important that all of the blades be adjusted equal amounts in unison, in that the entire mechanism is supported upon the concrete during the 'operation, that is, the prime mover, the frame, the mechanism supporting the blades and the blades themselves are supported upon the concrete that is being levelled or finished. That being the case, adjusting mechanism has been provided for adjusting all of the blades in unison. This adjusting mechanism will now be described.

As may be best seen in Figures 3 and 5, a shaft 70 extends through the. tubular housing members 42. The outer end of the shaft 70, as seen in Figure 5, is journalled in a bearing 72, press-fitted or otherwise mounted in the bracket 50. The inner end of the shaft 70, as best seen in Figure 3, is journalled in the bearing 74, press-fitted or otherwise mounted in the bore of the tubular portion 40. The shaft is rotatably mounted in the bearings 72 and 74. The shaft 70 near the outer end is provided with a transverse key or stud 76 projecting up through a slot 78 in the bracket 50. This bracket 50 is provided with a pair of apertures 80 and 82 threadedly receiving adjusting screws 84 engaging the transverse key or stud 76. Incidentally, the stud 76 threadedly engages the outer end of the shaft 70. By adjusting the screws 84, the relative angular position of the bracket 50 with respect to the shaft 70 may be adjusted. The key 76 projects into the shaft 70 between the end of the cylindrical housing members 42 and the bearings 72. 'By adjusting the screws 84, it is possible individually to adjust all of the blades to the same angle.

The inner end of the shaft 70 has mounted thereon a cam follower 90, held in adjusted position upon the shaft 70 by a pin or set screw 92, best seen in Figure 8. Each cam follower is provided with an arcuate cam engaging surface 94 engaging a washer 96 seated against the hub 98 of an adjusting wheel 100 having press-fitted therein a threaded bushing 102 threadedly engaging threads 104 on the shaft 30.

It can readily be seen that the angular position of the cam followers 90 may be adjusted by raising or lowering the wheel 100' on the shaft 30. Whenever the cam followers 90 are adjusted, the shafts 70 are also adjusted and the angle of inclination of the blades 60 is adjusted. By this arrangement, the adjustment of the wheel 100 adjust all of the blades 60 in unison. As the wheel 109 is actuated downwardly, the angle of inclination of the blades 60 is increased. As the wheel 106 is adjustedv upwardly on the shaft 30, the angle of inclination of the blades is decreased. When the surface to be smoothed or finished is receiving its initial machine troweling, the angle of inclination approaches zero degrees and, conversely, when the surface is receiving its finished machine troweling, the angle of blade inclination is increased.

Whenever an adjustment of the blades is desired, the rotation of the blades is stopped andthe wheel 100 adjusted to the position required to attain the proper angle of inclination of the blades.

As can best be seen in Figures 1 and 2, the outer edges of the blades 60 are located a short distance within the ring 18 which functions as a non-rotating guard against damage to walls, forms, or any projections through the surface being finished, as well as protection to the blades themselves and the machine operator. It is also clearly seen in Figire 2 that the ring 18 is near the finished surface when the blades 60 are adjusted, so as to lie in a substantially horizontal plane.

The integral tubular frame structure is strong and at the same time light in weight. tire troweling mechanism is fixedly attached at four points to this tubular frame structure. The frame structure provides operating and carrying handles, control mountings and protective bumpers. The troweling device may be of rotation. In other words, the weight of the prime mover and the gear box being centered above the drive shaft and this weight transmitted to the blades at the ends of the arms 42 results in a rigid, sturdy, long-lasting structure.

Although the preferred embodiment of the device has been described, it will be understood that within the purview of this invention various changes may be made in the form, details, proportion and arrangement of parts, the combination thereof and mode of operation, which generally stated consist in a device capable of carrying out the objects set forth, as disclosed and defined in the appended claims.

Having thus described my invention, I claim:

1. In a troweling machine a centrally disposed member mounted for rotation, said member including a disc portion forming a main body, and a plurality of hollow cylindrical portions equiangularly disposed and integral The balance of the en'- easily, safely and conveniently carried by the handle 12 and the auxiliary handle formed by the leading margin 10A of the frame 10. In so doing, the ring 18 protects the man from the hot engine. The troweling device is easily manipulated, due to the balanced condition. It is merely necessary to exert a proper force to the hand grip portions 14 to guide and control the movement of the troweling device. The troweling device may be guided or steered by the handle 12. When troweling, the troweling device may be moved gradually over the surface to be finished.

The weight of the machine is equally distributed to the center of the trowel blades, assuring better balance and ease of handling and operation. This duplicates hand" work, as a finisher holds the trowel in the center of the trowel and not by one end; The pressure is equally distributed to both ends and the middle of the blade. Thus, the trowel blades will wear evenly and have longer life. The bars are fixed and therefore cannot wear at a point where attached to the bracket; All other trowels have swivel spars, which allow wear to occur at a point close to the axis of rotation, which then allows the outer end of the blade to rise, transferring the weight to the inner end of the blade, resulting in uneven blade contact, wear and finishing.

All of the tilt adjusting parts shown herein are protected' from concrete being splashed upon them, which assures longer life, in that the concealed movable parts are protected from such splashing concrete and, therefore, protected from undue wear.

Due to the bracket 52 being attached to the bar 58 at an area that is concentric both with the longitudinal axis and the transverse axis of the trowel blade, anddue to the fact that the angular adjustment of the blade takes place at the outer end of the tubular member 42, wear ofi parts does not have as. serious elfects as though the trowel blades: were adjustably attached atv a point near the. axis with the disc portion, said hollow cylindrical portions being outwardly directed, the longitudinal axis of each of said tubular portions being offset from the axis of rotation of said centrally disposed member, a plurality of means for supporting a plurality of trowel blades, one means for each of said cylindrical portions, the longitudinal axis of the trowel blades being offset from the axis of rotation of said centrally disposed member on the side of the axis of rotation opposite from the side on which the longitudinal axis of the corresponding cylindrical portion is mounted, each. of said means including a tubular housing, each tubular housing being fixedly mounted at its inner end in the hollow cylindrical portion, a bracket rotatably mounted upon the outer end of the tubular housing and fixedly attached to the blade of the trowel, a shaft having its inner end extending through the tubular housing, means for fixedly attaching said bracket to the outer end of said shaft, said means including a pin fixedly mounted near the end of the shaft and located in the bracket, adjusting means including a pair of screws mounted in the bracket and engaging said pin to adjust the bracket with respect to the shaft to thereby adjust the angle of the blade with respect to the shaft, and means including a cam attached to the inner end of the shaft cooperating with an adjustable collar for adjusting the angle of the shaft and thereby adjusting the angle of the trowel blades, said collar being common to all of the shafts for adjusting the angle of the blades in unison.

2. In a troweling machine a centrally disposed member mounted for rotation, a plurality of tubular housings directed outwardly from said centrally disposed member, means for fixedly attaching the housings to the centrally disposed member, a plurality of brackets rotatably mounted on the outer ends of the housings, a plurality of trowel blades, means attaching the brackets to the centers of the trowel blades, means for adjusting the blades, said last mentioned means including a plurality of shafts, one for each of said housings, there being one shaft fixedly attached to each of the brackets and projecting through the tubular housing, and mechanism for adjusting the brackets and the trowel blades thereon in unison, said adjusting mechanism including a plurality of cams, one of which is mounted on the inner end of each shaft, said earns having an arcuate' cam engaging surface, and. a vertically adjustable collar for operating said cams in unison, and means for adjusting each blade with respect to its shaft, said last mentioned means including a radially disposed pin fixedly mounted in the outer end of the shaft and adjusting screws mounted in each bracket, said adjusting screws engaging said pin on opposite sides thereof to adjust the relative angular position of the blade with respect to its shaft.

3; In a troWeling machine, the combination including a centrally disposed disc-havinga plurality of equiangular cylindrical portions integral therewith, a plurality of housing assemblies, each of said housing assemblies in- 5 cluding one of said cylindrical portions integral with the disc, said cylindrical portion having a cylindrical cavity, a tubular sleeve mounted in said cavity and projecting outwardly from the cylindrical portion, a trowel blade supporting bracket mounted upon the outer end of the tubular sleeve, said bracket having a cylindrical cavity having mounted therein a shaft journalled in the bushing, said shaft extending through the tubular sleeve, said shaft being provided with a radial stud fixedly mounted near the outer end of the shaft, said stud being located between the bushing and the outer end of the tubular sleeve, and means accessible from the exterior of the bracket engaging said stud for adjusting the relative angular position of the bracket with respect to the shaft to thereby adjust the angular position of the trowel blade with respect to the shaft.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Engineering News-Record, May 19, 1955, page 52. 

